Small steam locomotive

Small steam locomotive - Assembly manual

Needed parts or materials (suggested, you can use other matches parts)

• 32 pieces M2.2x6.5 screw (DIN7981),
• several short pieces of filament 1.75 mm for hinges.

Optional parts and materials

• cyanoacrylate glue (if needed to attach the wheels to the axles),
• the locomotive is prepared for assembly of a set of lights (4*white LED 5 mm), you can also use white LEDs as an imitation of reflectors (even if you do not intend to connect them to the battery),
• to the project was added an additional boiler element, adapted for mounting two PCB 7*7 mm switch ON/OFF.

3D printing

• We recommend using a 0.4 mm nozzle and a 0.2 mm layer height, but feel free to try other settings. If you are printing with a child and your printer has no filters, consider using PLA filament because it generally produces relatively low emissions of harmful substances.
• All parts are positioned and ready to print, so you don't need to rotate them in your slicer. The parts are oriented for maximum strength, so don't change their orientation unless necessary.
• The elements are easy to print and do not require the use of supports, brims or rafts (the only exception is the wheel axles, they should be printed vertically. We recommend using a small brim).
• The model is designed and optimized for printing with 100% infill. We recommend using 100% infill for all parts, as the savings from reducing the infill are negligible.

Assembling of parts

• If you don't want to use LEDs, you can use TAY01-lamp.stl file instead.
• We have designed a special wheel and axle assembly tool, you can print it and use it to make your work easier.
• The wheel and axle dimensions are designed to fit together. However, if your printer produces them with too much play, try securing the wheels with a little glue. You can also very slightly chamfer the ends of the axles using an ordinary pencil sharpener. If an axle is too thick, you can gently file the hole in the wheel or make a very slight adjustment to the horizontal scale in your slicer, leaving the vertical scale at 1:1.
• Make sure the opposite wheels are turned 90 degrees (there is a small marker on the axles to help you with this). This is very important because if the angle on any of the axles is different, the wheels will jam.
• Try not to tighten the coupling rods coupling-rod.stl. They should be free and easy to spin. If the coupling rods are too tight, you can slightly enlarge the holes in them.
• Before assembly, be sure to check that the crosshead.stl crossheads move freely and without jamming along their guides crosshead-guide.stl. Getting the coupling rods to move freely may require some effort, but does not require complicated actions.
• Before assembling the cabin, check that the brake lever turns freely.
• Use pieces of filament 1.75 mm to attach doors and roof.

Maintenance

• Replaceable parts: The model consists of many separate parts. If a part is damaged, there is no need to print the entire model again. Check the instructions for the name of the damaged part, then print only that part and replace it in the model.
• Maintenance tip: Printed Toys locomotives and wagons are designed for hands-on play. A small amount of PTFE (Teflon) grease on the axles can reduce friction and help keep the model running smoothly. Lubrication can be done immediately after printing and repeated after extended use if needed. Regular maintenance can also be treated as an additional part of the play, adding some of the activities involved in maintaining real vehicles.

Compatibility with older versions

• On July 30, 2025, file names were changed because of a new unified file catalog. Archives, videos, and instructions were also updated. The models stayed the same — only the file names changed. If you use older archives, please watch the previous instruction video.
• On 26 June 2022, the coupler mounting method was changed to make the trains suitable for running on tracks. If you have models downloaded before this date, we recommend printing and installing the new versions of coupler-automatic.stl and coupler-automatic-cotter.stl on older wagons (these files are available, among other places, in the free locomotive models). If you do not use tracks, you do not need to print new parts - simply turn all couplers on older wagons upside down.

Assembly manual movie

Click to see assembly manual on Youtube.
Turn on subtitles (if available) to see part names. Do not use YouTube auto translate.
You can pause the movie and skip frames using "<" and ">" buttons from your keyboard.

License

This model is free to use.

You can:

• print an unlimited number of models,
• modify and print modified files,
• print models for a gift,
• use printed models for free education.

You can not:

• use models for earn money,
• sell printed models,
• sell any stl files (original or modified),
• publish or distribute any stl files.